Eliminate LCD Motion Blur on Samsung 120 Hz Monitors

Samsung SA700D, SA750D, and SA950D has a little-known strobe backlight similar to LightBoost that eliminate LCD motion blur. Samsung does not advertise this as an official LightBoost feature. A synchronized stroboscopic backlight works by keeping pixel persistence in total darkness (unseen by eye) between refreshes, and strobing the backlight only on fully-refreshed LCD frames (high speed video). As a result, the refresh-synchronized strobe backlight eliminate LCD motion blur. This brings CRT motion clarity to LCD displays.

The good news is that the Samsung strobe backlight works with both AMD Radeon and nVidia Geforce cards! (Credit: CyberGamer.com.au review).

PixPerAn tests and TestUFO tests show 75% less LCD motion blur than regular Samsung 120 Hz even for 2D usage, which is a huge reduction. PixPerAn readability test of at least 25. This is an additional reduction on top of the 50% motion blur elimination caused by going from 60 Hz to 120 Hz. As a result, you get almost a whopping 90% less LCD motion blur than regular 60Hz! This is because the Samsung 3D mode enables a strobe backlight, which also eliminates motion blur during 2D usage.

The bad news is that the input lag is worse than official LightBoost monitors, so this is not as useful for competition online gaming as official LightBoost monitors. However, the lack of motion blur is quite handy for solo gaming, and the Samsung is known to have better colors than most TN-panel monitors!

The Science Behind Strobe Backlights

The Samsung strobe backlight is almost identical to LightBoost. This high speed video (480fps + 1000fps) demonstrates a LightBoost strobe backlight successfully bypassing pixel persistence as the motion blur barrier:

30 Responses to Samsung HOWTO

I have heard from additional testers. The Samsung S23A700D apparently has the strobe backlight for 3D that works in 2D too!
Edit: It appears that all 700D, 750D, and 950D series all appear to have the strobe backlight feature, based on further testing reports. Please post your PixPerAn test success reports!

Posted with permission, a testimonial from a competition gamer, sent to me by email:

Hi Mark,

I got really excited when I saw your update about two of the Samsung 3d monitors being capable of better motion performance without the need for a Geforce card. I just successfully tested my S23a700D and it worked so this one can be added to the list as well. I was able to get up to a tempo of 25 or so on the pixperan readability test and still make out the individual letters.

The only problem is that the screen dims, and I get an added 20-30ms of input lag that makes mouse movements feel a bit “soupy”. I play Quakeworld online (usually at 600 fps to reduce tearing-no vsync) and actually found even with the added input lag, I was able to track other players much easier and pull of twitch shot kills that I normally wouldn’t because of the blur I normally get when spinning 180 degrees quickly. It would be incredible if someone could somehow hack the firmware of these monitors to remove the input lag, with some brightness/color tweaking I’d leave this mode on all the time.

Thanks for you continued research, look forward to this becoming a feature of lcd’s in the future. It really removes that last barrier to crt-like performance.

Matt

NOTE: There are other models (e.g. BENQ XL2411T) that eliminate this huge added input lag, so you can get the best of all worlds!

I can confirm that this also works on the S27A750D. I believe another user reported otherwise (perhaps on an S23A750D) but there is no reason why it wouldn’t work on the SA750 series. I have confirmed subjectively and using an evaluation of the MER performance.

Exciting!!!
I will test zero motion blur with my S23A700D and hd6850 display card this night.
But I want to know the reason that change “Response Time” to “Normal” via the monitor OSD in step 2. May I change to “Fastest” option for lower reponse time.
Furthermore, please give me some advice to reduce the input lag in 2D FPS games. Thanks.

Unfortunately, there are some nasty motion artifacts that show up if you use a “Response Time” of Fastest. The pixel response need to be optimized with the timing of the strobe backlight, which hides most of the pixel response curve in total darkness, between backlight strobes.

If you want the fastest response, least motion artifacts, and minimum input lag with a strobe backlight, I highly recommend one of the new 1ms monitors (BENQ XL2411T or ASUS VG248QE).

Did you ever find a solution for this. I just got 3 samsung S23A700D and every time i turn off and on my pc or monitors, or just put the pc to sleep. The monitors all turn off frame sequential mode. Theres no way everytime i turn my pc im going to go into 3 monitors OSD and turn it on, so i need to find a solution or im selling them.

I have a Samsung S27A950D. Do I understand it correctly that I only have to set the settings above in the OSD of the monitor to have the strobe backlight turned on and I don’t have to set anything in the nVidia Control Panel?

Is this correct? Or even if I have a Samsung monitor I still have to do the trick with ToastyX’ utility and the NCP?

ToastyX Strobelight is not needed for Samsungs.
Samsung 3D mode is so easy to enable via monitor menus.

ToastyX Strobelight was invented for nVidia LightBoost, only because nVidia bundled LightBoost motion blur elimination tightly with 3D Vision. It used to be difficult to turn on LightBoost for people who didn’t have 3D Vision. ToastyX Strobelight unbundles the motion blur elimination feature of LightBoost, away from 3D stereoscopic, allowing you to easily turn it on/off, without requiring a 3D Vision Kit (or even 3D Vision drivers, for that matter). For more information, see the LightBoost FAQ.

P.S. I helped ToastyX make Strobelight compatible with BENQ — so you also have me to thank too, if you’re using Strobelight on a BENQ monitor.

Is the added input lag from the Samsung with Lightboost that bad?! I mostly play fast FPS games and if it’s clearly noticeable it would be a major disadvantage as the main point of going with a 120Hz monitor is to have as less input lag possible, unless you guys tell me that the refresh rate have nothing to do with the input lag, neither does the “GtG value”, that it’s just a spec that the manufacturer never tell and that you cannot improve no matter what you do on the monitor.

NCX:s review of the monitor says: “2D-3D Conversion introduces a lot of input lag which affects aiming, movement and general reactivity during games. When using a controller it is still playable, but I found the delay to be unbearable when gaming with a keyboard and mouse.”

They are actually separate components:
– 2D-3D conversion from the GPU perspective can entail some input latency overheads. Alternate-frame rendering can also entail some input latency issues as well.
– Strobing from the Computer monitor perspective can also introduce input latency that occurs independently of 3D conversion. This is not covered by NCX.

The bottom line is that “3D Mode” from the Samsung monitor perspective, isn’t doing 2D-3D conversion when viewing in 2D mode. However, the response time adjustment adds input lag on Samsung, and is the major cause of added input lag during “3D Mode”. This is shown by turning off 3D mode, changing Response Time settings, and going back into 3D mode — you get a bit less input lag but more motion artifacts when viewing http://www.testufo.com … So a lot of Samsung’s input lag during the monitor-side “3D Mode” setting, is actually caused by the optimal-appearing Response setting. This is somewhat unfortunate, as both ASUS/BENQ doesn’t add any further input latency except for the minimum half frame average input lag that strobing entails (due to waiting for the refresh to finish before the strobe).

I recently got 3 samsung sa700d monitors. I followed the samsung light boost how to instructions from the blurbusters. I can turn the frame sequential mode on and it works great, totally reduces the motion blur. My problem is if I turn off the monitors or my computer, then the monitors turn off that mode. I tried researching it more but everything I read is people using that CRU program to import inf. so that they can get 3d vision working. I dont know if that will help me because the option to turn it on and off is in the monitor osd. I ran the toastyx program hoping I could just force strobbed refresh rates all the time but it didnt make a difference. Do you have any ideas on how to get it to stay in frame sequential mode?

If this works, then it is possible to have an easy utility that transmits these commands to all the monitors every time the computer wakes up, or via an easy icon click. But before this, can you at least test these commands?

both times it said checksum error.
I for sure have an issue with one of the monitors. 2 of them lets me connect via DVI and the computer knows they are samsung s23a700 monitors but the one monitor I have just goes black when i connect via dvi. When I connect that monitor with dvi to a active dual link display port adapter then display port to my video card. Then it will display 640×480 but it doesnt know what kind of monitor it is. With the CRU1.1 utility I exported the stuff from the samsung monitor and then imported it to the Generic pnp monitor and then changed product id. I now had my computer recognizing all the monitors as samsungs and it let me set them all to 120hz.

Then I tried to set up nvidia surround, but the screens just go blank, when i click apply. I read online to download .inf drivers for a dell alienware 2310 and install. I tried that and now it allows me to get into nvidia surround mode.
I dont know if any of that will interfere with what your having me test.

Hi blurbuster, I have a quick question. I have a Samsung S23A700D. I did all the steps you mention above and in the final step where you run a test on testufo.com, my frame rate is only 40fps and the refresh rate is at 40hz. It also says “VALID” on the bottom of the page.

Is that the result that you suppose to get on testufo.com? Or am I supposed to get 120fps and 120hz?

Hello Chief,
I own a SA950D plugged in through a DisplayPort and have applied your tutorial which resulted in a fairly dim screen.
Is this fix absolutely required to have an acceptable 120Hz experience (is it something I can ignore?)